The Neurologic AIDS Research Consortium (NARC) will maintain an effective collaborative clinical study group dedicated to the study of HIV-associated neurologic disease. Projects are identified by investigators, designed with review by internal and external experts and implemented. This proposal includes completion of currently active studies, and initiation of new areas of investigation relevant to the neurologic complications associated with HIV infection. The specific projects to be undertaken include: 1. Complete and analyze A5090 testing the safety and efficacy of transdermal selegiline for HIV- associated motor cognitive disorder; 2. Monitor the incidence, prevalence and natural history of HIV related neuropathy and neuropsychologic disorders and validate brief screens for detection of central and peripheral nervous system dysfunction in the Adult Longitudinal Linked Retroviral Treatment (ALLRT) Cohort of the AIDS Clinical Trial Group; 3. Complete and analyze longitudinal physiologic and morphologic characterization of distal sensory neuropathy in HIV over a one year period of observation; 4. Complete and analyze our study of the virologic, immunologic and pharmacologic manifestations of HIV in CSF compartment during anti-retroviral treatment; 5. Perform a study of Acetyl L-carnitine for treatment of dideoxynucleoside induced painful neuropathy in HIV infection; 6. Develop and implement a study to measure the safety, tolerability and analgesic properties of Prosaptide for HIV-associated painful peripheral neuropathy; and 7. Characterize the newly described acute neuromuscular disorder associated with lactic acidosis seen in treated HIV patients. Major studies will be developed and operated cooperatively with the AIDS Clinical Trial Group (ACTG). The NARC will continue to develop a broad agenda for clinical study of neuroAIDS complications following these studies, directed by the Principal Investigator, Executive Steering committee and the NINDS appointed Data and Safety Monitoring Board (DSMB).